CN121059880A - A hydrogel dressing and its preparation method - Google Patents
A hydrogel dressing and its preparation methodInfo
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- CN121059880A CN121059880A CN202511364252.7A CN202511364252A CN121059880A CN 121059880 A CN121059880 A CN 121059880A CN 202511364252 A CN202511364252 A CN 202511364252A CN 121059880 A CN121059880 A CN 121059880A
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- hydrogel dressing
- hyaluronic acid
- water
- silk fibroin
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Abstract
本发明公开了一种水凝胶敷料及其制备方法，属于医药技术领域。本发明的水凝胶敷料配方按质量百分数计包括：聚乙烯醇5~10%、改性透明质酸0.5~3%、丝素蛋白0.1~0.2%、姜糖酯B 0.1~0.5%、黄原胶0.5~3%、甘油0.5~1%，余量为水。本发明提供的水凝胶敷料，通过添加含咪唑基团和二硫键的改性透明质酸，实现了抗菌与抗瘢痕的双重功效，加速伤口愈合。此外，本发明引入的丝素蛋白表面富含带正电荷的精氨酸/赖氨酸残基，姜糖酯B通过调节膜流动性促进血小板初期活化，与丝素蛋白形成氢键网络，共同构建三维促凝支架。两者协同作用能够显著缩短止血时间，促进伤口愈合。
This invention discloses a hydrogel dressing and its preparation method, belonging to the field of pharmaceutical technology. The hydrogel dressing formulation of this invention comprises, by mass percentage: 5-10% polyvinyl alcohol, 0.5-3% modified hyaluronic acid, 0.1-0.2% silk fibroin, 0.1-0.5% gingerol ester B, 0.5-3% xanthan gum, 0.5-1% glycerin, with the balance being water. The hydrogel dressing provided by this invention, by adding modified hyaluronic acid containing imidazole groups and disulfide bonds, achieves dual antibacterial and anti-scarring effects, accelerating wound healing. Furthermore, the silk fibroin introduced in this invention is rich in positively charged arginine/lysine residues on its surface, and gingerol ester B promotes initial platelet activation by regulating membrane fluidity, forming a hydrogen bond network with silk fibroin to jointly construct a three-dimensional procoagulant scaffold. The synergistic effect of both significantly shortens hemostasis time and promotes wound healing.
Description
Technical Field
The invention belongs to the technical field of medicines, and particularly relates to a hydrogel dressing and a preparation method thereof.
Background
Traditional dressings, such as gauze or bandages, are single in function, provide a physical barrier for wounds while absorbing small amounts of blood exudates, and are difficult to cooperatively solve multiple challenges in the wound healing process, particularly in terms of high-standard requirements for chronic wounds and cosmetic repair.
In contrast, hydrogel dressings, which are an emerging wound care material, exhibit significant advantages in clinical applications by virtue of their unique high water content, controllable swelling properties, and three-dimensional network structure of biomimetic extracellular matrix. The material not only can form an isolation barrier through physical encapsulation, but also can realize function expansion through drug loading or bioactive molecules, thereby providing more comprehensive support for wound healing. The hydrogel dressing in the current market is mainly based on natural high polymer materials (such as hyaluronic acid and chitosan) or synthetic polymers (such as polyethylene glycol), and has certain moisture retention property and biocompatibility, but is difficult to simultaneously meet multiple requirements of infection, bleeding, scar prevention and the like, so that multiple dressings are used in a clinical mode in a superposition mode, operation complexity and nursing cost are increased, and overall curative effect is possibly influenced. Therefore, there is a need to develop a multifunctional hydrogel dressing to solve the above problems.
Disclosure of Invention
In order to overcome the defects in the prior art, one of the purposes of the invention is to provide a hydrogel dressing. The invention provides a hydrogel dressing with antibacterial, anti-scar and hemostatic functions. The core of the wound healing agent is that modified hyaluronic acid containing imidazole groups and disulfide bonds is introduced, silk fibroin and ginger sugar ester B are compounded, and wound healing is promoted together through multicomponent synergistic effect.
It is a further object of the present invention to provide a method for preparing a hydrogel dressing.
One of the purposes of the invention is realized by adopting the following technical scheme:
The hydrogel dressing comprises, by mass, 5-10% of polyvinyl alcohol, 0.5-3% of modified hyaluronic acid, 0.1-0.2% of silk fibroin, 0.1-0.5% of ginger sugar ester B, 0.5-3% of xanthan gum, 0.5-1% of glycerol and the balance of water.
Further, the preparation method of the modified hyaluronic acid comprises the following steps:
(1) Dissolving hyaluronic acid and 2- ((2-bromoethyl) dithio) ethanol in water, then adding EDC hydrochloride and DMAP to react, dialyzing, and freeze-drying to obtain an intermediate 1;
(2) Dissolving the intermediate 1 in water, adding an ethylene glycol dimethyl ether solution of a compound A, potassium carbonate and PdCl 2, heating under the protection of nitrogen for reaction, dialyzing, and freeze-drying to obtain modified hyaluronic acid;
the chemical structural formula of the compound A is 。
Further, in the step (1), the dosage ratio of the hyaluronic acid, the 2- ((2-bromoethyl) dithio) ethanol, the EDC hydrochloride, the DMAP and the water is 0.5g:0.08-0.12g:0.6-0.8g:0.3-0.7g:100-150mL.
Further, in the step (1), the molecular weight of hyaluronic acid is 100kDa to 200kDa.
Further, in the step (1), the reaction time is 1-2d.
Further, in the step (2), the dosage ratio of the intermediate 1, the compound A, the potassium carbonate, the PdCl 2, the water and the ethylene glycol dimethyl ether is 0.15-0.25g:0.2g:0.15-0.3g:0.03-0.08g:150-200mL:45-50mL.
Further, in the step (2), the temperature of the reaction is 45-50 ℃ and the time is 24-36h.
The second purpose of the invention is realized by adopting the following technical scheme:
the preparation method of the hydrogel dressing comprises the following steps:
s1, adding polyvinyl alcohol into two thirds of the water, heating to be completely dissolved, cooling to room temperature, adding modified hyaluronic acid, xanthan gum and glycerol, and uniformly stirring to obtain a gel matrix for later use;
S2, taking one third of the weight of water, adding silk fibroin and ginger sugar ester B, and uniformly stirring to obtain a mixed solution for later use;
s3, adding the mixed solution obtained in the step S2 into the gel matrix obtained in the step S1, uniformly mixing, and carrying out irradiation sterilization to obtain the hydrogel dressing.
Further, the heating temperature in step S1 is 85-95 ℃.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention provides a hydrogel dressing which has the functions of resisting bacteria and scars and shortening hemostatic time. The modified hyaluronic acid containing imidazole groups and disulfide bonds has the dual effects of resisting bacteria and resisting scars, namely, on one hand, the weak alkalinity of the imidazole rings can destroy lipid bilayer structures of bacterial cell membranes, meanwhile chelate metal ions (such as Fe 3+、Zn2+) necessary for bacterial metabolism, double block microbial proliferation and endow dressing with excellent antibacterial property, and on the other hand, the dynamic reversible property of the disulfide bonds can remove excessive Reactive Oxygen Species (ROS) at wound sites, relieve oxidative stress injury, and combine inherent anti-inflammatory and moisturizing properties of the hyaluronic acid, so that wound healing can be accelerated, and the generation of scars can be effectively reduced.
In addition, silk fibroin and ginger sugar ester B are added into the hydrogel dressing, and the synergistic effect of the silk fibroin and the ginger sugar ester B can obviously shorten the hemostatic time and promote wound healing, and the surface of the silk fibroin is rich in arginine/lysine residues with positive charges, so that erythrocytes and platelets with negative charges can be specifically enriched, and the rapid positioning of blood coagulation factors can be realized. Meanwhile, the hydrophobic alkyl chain of the ginger sugar ester B can be inserted into a platelet membrane phospholipid bilayer, the initial activation of platelets is promoted by regulating the fluidity of the membrane, the glycosyl structure of the ginger sugar ester B can form a hydrogen bond network with the beta-sheet domain of silk fibroin, a three-dimensional coagulation promoting bracket is constructed together, and the hemostasis process is accelerated cooperatively.
2. The invention also provides a preparation method of the hydrogel dressing, which has simple operation steps and is beneficial to industrial production.
Drawings
FIG. 1 is an infrared spectrum of a modified hyaluronic acid obtained in example 1 of the present invention.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and detailed description, wherein it is to be understood that, on the premise of no conflict, the following embodiments or technical features may be arbitrarily combined to form new embodiments. The specific conditions not specified in the examples were carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used, unless otherwise specified, are all conventional products obtained from commercial sources.
In the invention, the molecular weight of the polyvinyl alcohol Mw9000-10000, the molecular weight of the water-soluble silk fibroin 6-10kDa and the molecular weight of the hyaluronic acid 100-200kDa.
Example 1
The hydrogel dressing comprises, by mass, 8% of polyvinyl alcohol, 2% of modified hyaluronic acid, 0.1% of water-soluble silk fibroin, 0.3% of ginger sugar ester B, 2% of xanthan gum, 0.8% of glycerol and the balance of distilled water.
The preparation method of the modified hyaluronic acid comprises the following steps:
(1) Adding hyaluronic acid and 2- ((2-bromoethyl) dithio) ethanol into deionized water for fully dissolving, then adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC hydrochloride) and 4-Dimethylaminopyridine (DMAP), wherein the dosage ratio of the hyaluronic acid, the 2- ((2-bromoethyl) dithio) ethanol, the EDC hydrochloride, the DMAP and the deionized water is 0.5g:0.1g:0.7g:0.5g:120mL, and after reacting for 1.5 days at room temperature, dialyzing for 2 days, and freeze-drying to obtain an intermediate 1;
(2) Dissolving the intermediate 1 in deionized water, adding an ethylene glycol dimethyl ether solution of a compound A (CAS: 2135512-71-7), potassium carbonate and PdCl 2, wherein the dosage ratio of the intermediate 1 to the compound A, the potassium carbonate to the PdCl 2 to the deionized water to the ethylene glycol dimethyl ether solution is 0.2g to 0.25g to 0.05g to 180mL to 48mL, reacting for 36h under the protection of nitrogen, dialyzing for 2 days, and freeze-drying to obtain the modified hyaluronic acid.
The infrared spectrum of the modified hyaluronic acid is shown in figure 1. The characteristic peak of carboxyl hydroxyl group at 3500cm -1 of modified hyaluronic acid is obviously weakened compared with that of hyaluronic acid, and the characteristic absorption peaks of imidazole ring C=N bond and C-S bond appear at 1580cm -1 and 650cm -1 respectively, which indicate successful preparation of modified hyaluronic acid.
This example 1 also provides a method for preparing the hydrogel dressing described above, comprising the steps of:
s1, taking two thirds of the weight of distilled water, adding polyvinyl alcohol, heating to be completely dissolved at 90 ℃, cooling to room temperature, adding modified hyaluronic acid, xanthan gum and glycerol, and uniformly stirring to obtain a gel matrix for later use;
s2, taking one third of distilled water by weight, adding water-soluble silk fibroin and ginger sugar ester B, and uniformly stirring to obtain a mixed solution for later use;
s3, adding the solution obtained in the step S2 into the gel matrix obtained in the step S1, uniformly mixing, and performing irradiation sterilization to obtain the hydrogel dressing.
Example 2
The hydrogel dressing comprises, by mass, 5% of polyvinyl alcohol, 0.5% of modified hyaluronic acid, 0.1% of water-soluble silk fibroin, 0.1% of ginger sugar ester B, 0.5% of xanthan gum, 0.5% of glycerin, and the balance of distilled water.
The preparation method of the modified hyaluronic acid comprises the following steps:
(1) Adding hyaluronic acid and 2- ((2-bromoethyl) dithio) ethanol (CAS: 113398-38-2) into deionized water for full dissolution, then adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC hydrochloride) and 4-Dimethylaminopyridine (DMAP), wherein the dosage ratio of hyaluronic acid, 2- ((2-bromoethyl) dithio) ethanol, EDC hydrochloride, DMAP and deionized water is 0.5g:0.08g:0.6g:0.3g:100mL, reacting for 1 day at room temperature, dialyzing for 2 days, and freeze-drying to obtain an intermediate 1;
(2) Dissolving the intermediate 1 in deionized water, adding an ethylene glycol dimethyl ether solution of a compound A (CAS: 2135512-71-7), potassium carbonate and PdCl 2, wherein the dosage of the intermediate 1, the compound A, the potassium carbonate, the PdCl 2, the deionized water and the ethylene glycol dimethyl ether solution is 0.15g:0.2g:0.15g:0.03g:150mL:45mL, and carrying out dialysis for 3 days after the reaction for 32h under the protection of nitrogen, and carrying out freeze drying to obtain the modified hyaluronic acid.
This example 2 also provides a method for preparing the hydrogel dressing described above, comprising the steps of:
S1, taking two thirds of the weight of distilled water, adding polyvinyl alcohol, heating to be completely dissolved at 85 ℃, cooling to room temperature, adding modified hyaluronic acid, xanthan gum and glycerol, and uniformly stirring to obtain a gel matrix for later use;
s2, taking one third of distilled water by weight, adding water-soluble silk fibroin and ginger sugar ester B, and uniformly stirring to obtain a mixed solution for later use;
s3, adding the solution obtained in the step S2 into the gel matrix obtained in the step S1, uniformly mixing, and performing irradiation sterilization to obtain the hydrogel dressing.
Example 3
The hydrogel dressing comprises 10 mass percent of polyvinyl alcohol, 3 mass percent of modified hyaluronic acid, 0.2 mass percent of water-soluble silk fibroin, 0.5 mass percent of ginger sugar ester B, 3 mass percent of xanthan gum, 1 mass percent of glycerol and the balance of distilled water.
The preparation method of the modified hyaluronic acid comprises the following steps:
(1) Adding hyaluronic acid and 2- ((2-bromoethyl) dithio) ethanol into deionized water for fully dissolving, then adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC hydrochloride) and 4-Dimethylaminopyridine (DMAP), wherein the dosage ratio of hyaluronic acid to 2- ((2-bromoethyl) dithio) ethanol to EDC hydrochloride to DMAP to deionized water is 0.5g:0.12g:0.8g:0.7g:150mL, and after reacting for 2 days at room temperature, dialyzing for 3 days, and freeze-drying to obtain an intermediate 1;
(2) Dissolving the intermediate 1 in deionized water, adding an ethylene glycol dimethyl ether solution of a compound A (CAS: 2135512-71-7), potassium carbonate and PdCl 2, wherein the dosage ratio of the intermediate 1 to the compound A, the potassium carbonate, the PdCl 2 to the deionized water to the ethylene glycol dimethyl ether solution is 0.25g:0.2g:0.3g:0.08g:200mL:50mL, reacting for 24 hours under the protection of nitrogen, dialyzing for 3 days, and freeze-drying to obtain the modified hyaluronic acid.
This example 3 also provides a method for preparing the hydrogel dressing described above, comprising the steps of:
S1, taking two thirds of the weight of distilled water, adding polyvinyl alcohol, heating to be completely dissolved at 95 ℃, cooling to room temperature, adding modified hyaluronic acid, xanthan gum and glycerol, and uniformly stirring to obtain a gel matrix for later use;
s2, taking one third of distilled water by weight, adding water-soluble silk fibroin and ginger sugar ester B, and uniformly stirring to obtain a mixed solution for later use;
s3, adding the solution obtained in the step S2 into the gel matrix obtained in the step S1, uniformly mixing, and performing irradiation sterilization to obtain the hydrogel dressing.
Comparative example 1
This comparative example 1 is substantially identical to example 1 except that the modified hyaluronic acid is replaced with hyaluronic acid, and the other is substantially identical to example 1.
Comparative example 2
This comparative example 2 is substantially identical to example 1 except that the ginger sugar ester B is replaced with silk fibroin, and otherwise is substantially identical to example 1.
Comparative example 3
This comparative example 3 is substantially identical to example 1 except that the silk fibroin is replaced with ginger sugar ester B, and otherwise substantially identical to example 1.
Test example 1
Preparing colibacillus liquid and staphylococcus aureus liquid with the concentration of 10 6 CFU/mL, taking the products obtained in examples 1 to 3 and the products obtained in comparative examples 1 to 3, dripping 500 mu L of each bacterial liquid on the surfaces of the products, covering a cover glass, culturing for 24 hours in a 37 ℃ constant temperature and humidity incubator, taking out the products, respectively adding 20mL of sterilized PBS (phosphate buffered saline) flushing product and the cover glass, shaking uniformly, taking 100 microliters, inoculating the products into beef extract peptone culture medium, culturing for 24 hours in the 37 ℃ constant temperature and humidity incubator, observing and counting the colony count, taking the bacterial count as an experiment group, simultaneously setting sterile water as a control group, and calculating the bacterial count of the products 1 to 3 and the bacterial count of the comparative examples 1 to 3 according to a formula, wherein the bacterial count= (the colony count of the control group-the experiment group)/the colony count of the control group is multiplied by 100%.
From the detection results in table 1, the hydrogel dressing of the invention has good antibacterial rate against escherichia coli and staphylococcus aureus. Among them, the antibacterial properties of examples 1 to 3 are superior to those of comparative examples 1 to 3, the antibacterial properties of comparative example 1 are the worst, and the antibacterial properties of comparative examples 2 and 3 are relatively good. The above results may be attributed to the change in the components in the formulation of the hydrogel, wherein comparative example 1 replaces the modified hyaluronic acid with the normal hyaluronic acid, resulting in a significant decrease in bacteriostatic effect.
Test example 2
To evaluate wound healing properties of the dressings obtained in examples 1 to 3, comparative examples 1 to 3, the following animal experiments were conducted:
60 healthy male SD rats (220-240 g in weight) were selected and randomly divided into 6 groups. All rats were anesthetized by intraperitoneal injection of 60mg/kg of sultai, shaved on the back and fed adaptively for 3d, and the back of the mice was wound with a 1cm diameter trephine to create a defective wound, and each of the rats was covered with a corresponding set of hydrogel dressings, and replaced twice daily.
(1) Hemostatic performance evaluation after dressing covering, the wound surface was gently absorbed by a filter paper strip until no blood oozed, and the time required from dressing covering to complete hemostasis, i.e., the time to hemostasis, was recorded, and the results are shown in table 2.
(2) Determination of residual area of wound surface the behavior and wound surface condition of rat were observed daily after operation, the residual area of wound surface was measured on day 14, and the data were recorded, and the results are shown in table 2.
(3) Scar hyperplasia assessment after healing, the vertical height from the highest point of the scar protrusion to the subcutaneous muscle tissue (H 1) and the vertical height from normal skin around the scar to the subcutaneous muscle (H 2) were measured, and the scar hyperplasia index = H 1/H2 was calculated and the results are shown in table 3.
From the test results in table 2, the hydrogel dressing of the present invention has excellent effects in shortening the hemostatic time and promoting wound healing. Among them, the effects of examples 1 to 3 are superior to those of comparative examples 1 to 3. Comparative example 2 uses silk fibroin to replace ginger sugar ester B, comparative example 3 uses ginger sugar ester B to replace silk fibroin, and the hemostatic time of the two is increased, which shows that silk fibroin and ginger sugar ester B in the hydrogel dressing have important roles in shortening hemostatic time. The rats of comparative examples 1 to 3 all showed different increases in the wound residual area, wherein the wound residual area of comparative example 1 was relatively large, indicating that the effect of the modified hyaluronic acid in promoting wound healing was more prominent.
As can be seen from the test results in Table 3, examples 1-3 are effective in reducing the scar hyperplasia index as compared with comparative examples 1-3. The components of the hydrogel dressing are changed in comparative examples 1-3, wherein the scar indexes of comparative examples 2 and 3 are obviously increased, which indicates that the scar indexes of the hydrogel dressing and the hydrogel dressing are poor in inhibiting scar hyperplasia, and compared with comparative example 1 and example 1, the hydrogel dressing has smaller difference and lower scar hyperplasia index, and the results indicate that the hydrogel dressing of examples 1-3 has positive effects on resisting scar production, and the modified hyaluronic acid has good antioxidant, antibacterial, anti-inflammatory and moisturizing effects, can accelerate wound healing and reduce scar hyperplasia.
The above embodiments are only preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, but any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention are intended to be within the scope of the present invention as claimed.
Claims (9)
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